1. Field of the Invention
The present invention is directed to the treatment of liquid waste. More specifically, but without limitation thereto, the present invention is directed to devices for processing liquid waste to remove substances that may impair the functioning of waste disposal utilities such as sewage treatment plants and sewage pumping stations inside a grease interceptor or grease vault.
2. Description of Related Art
Food service establishments typically produce liquid waste in the form of fats, oils and grease, commonly referred to as “FOG.” Because discharging FOG directly into the sewer system is undesirable and generally prohibited, a grease interceptor or grease vault is commonly installed to remove FOG from waste water prior to discharging the waste water into the municipal sewer system. Depending on the amount of FOG and other waste ingredients contained in the liquid waste, the grease interceptor fills with insoluble solids that need to be pumped out of the grease interceptor, typically several times a year.
The insoluble FOG liquid waste mixture is generally removed to a landfill, processed at a suitable wastewater treatment plant, or reprocessed into non-toxic byproducts. As grease interceptors rely on gravity separation—the lighter substances like FOG float to the top—most regulatory agencies require now proof that any process employed in a grease interceptor does not interfere with the designed and certified gravity separation process of any existing or new grease interceptor. As a result full or partial aeration of a grease interceptor is prohibited. Only if definite proof exists that no interference with gravity separation or retention time is achieved is approval given.